Question

In some horse populations, blindness can be a common trait. Let’s assume this trait is controlled by one gene, where dominant allele B produces a normal sighted horse and recessive allele b leads to blindness in homozygosity. A wild horse researcher determines that the frequency of blind horses in a specific population of wild horses in Nevada is 0.04.

Which of the following scenarios would make the wild horse population of Nevada no longer in Hardy-Weinberg equilibrium for the blindness trait?

Group of answer choices

a) Public land managers bring in 100 new horses all with normal vision from other wild populations each year

b) All of these scenarios would bring the population out of equilibrium

c) There is no preferred mating between normal vision and blind horses in the population

d) The population is able to thrive in their environment and stays very large

Answer 1

Correct answer is Option a) Public land managers bring in 100 new horses all with normal vision from other wild populations each year.

Explanation :

Hardy - Weinberg equilibrium is a theory stating that the variation in genetic entities such as allele frequency will be constant from one generation to next generation only when the following conditions are fufilled :

a. The population is infinitely large.

b. Mating within the population is random

c. There is no mutation events in the population

d. There is no migration of individuals into or out of the population.

e. Natural selection is not acting on the population.

Violation of any of these conditions, leads to the deviation ifrom Hardy-Weinberg :equilibrium

Option a is the correct answer since here the Hardy-Weinberg equilibrium for blindness trait will deviate due to the migration of 100 new individuals into the popoulation.

Option b is incorrect since not all the scenarios would bring the population out of equilibrium

Option c is incorrect since absence of preferred mating equates to random mating and it is not a violation of Hardy-Weinberg equilibrium conditions.

Option d is incorrect since presence of a large population fufills one of the conditions required to maintain Hardy-Weinberg equilibrium.

PS - Natural selection can be referred to as the differential survival and reproduction of individuals in a population due to variation in traits.

Migration can be defined as the movement of individuals from one habitat to another.

Mutation can be defined as the random change in the nucleotide sequence of a nucleic acid.